The present invention is related to an endoprosthesis to be implanted in the body of a user as a substitute for a removed portion of a tract of the user in general, and more particularly to an endoprosthesis which substitutes for the distal end of the digestive track of the user portions of whose small or large intestine have been operatively removed.
It is well known that, in connection with some ailments, such as intestinal cancer, it is sometimes necessary to remove portions of the digestive tract of a patient, such as portions of the small intestine or portions of the large intestine. Under these circumstances, it is sometimes necessary to also remove the rectal portion of the colon, including the anal sphincter. Thus, alternate means must be found for the removal of the feces from the body of the user.
One of the techniques which have been heretofore used to solve this problem was to give the patient whose intestinal parts or rectum had to be removed an abdominal substitute rectum. An article entitled "Komplikationen der Ileostomie und Colostomie und ihre Behandlung" (Complications of the Ileostomy and Colostomy and their Treatment), appearing in the magazine "Der Chirurg", Vol. 47 (1976), No. 1, pp. 16 to 21 discusses the psychological problems for the patient and the encountered complications when this operative procedure is resorted to. In this connection, it is to be mentioned that the ileostomy or the colostomy do not involve the use of a colonic endoprosthesis; rather, they involve an opening of the frontal abdominal wall, and the connection of the distal end of either the large intestine or the small intestine to the frontal abdominal wall at such an opening.
A continent ileostomy has been introduced by N. G. Kock in the passage entitled "Continent Ileostomy" appearing in "Progress in Surgery", vol. 12, pp. 180 to 201, published by Karger-Verlag in Basel in 1973. This publication describes the formation of a reservoir from a portion of a small intestine which aids in the discharge of the digested matter from the body of the user. This reservoir is arranged upstream of the per se unnatural substitute rectum which opens onto the abdominal wall. Even here, the solution does not involve any colonic endoprosthesis inasmuch as, first of all, the reservoir is formed from a natural tissue of the body of the user and, secondly, it does not take the place of the colon so that it neither replaces, nor permits the removal of, the abdominal rectum.
Even the "Kontinente Kolostomie durch Magnetverschluss" (Continent colostomy by a Magnetic Closure) disclosed by Feustel and Hennig in the "Deutschen Medizinischen Wochenschrift" (German Medical Weekly), No. 100, May 1975, pp. 1063 and 1064, does not involve the use of a colonic endoprosthesis; rather, it reveals a particularly progressive kind of the closure for an otherwise known abdominal rectum. According to this publication, a magnetic ring is implanted under the skin or under the mucous membrane at the abdominal wall, and a permanently magnetic lid having a centrally located plug closes the discharge opening in the abdominal wall due to the magnetic attraction between the lid and the implanted magnetic ring. Even here, no colonic endoprosthesis is involved inasmuch as there is provided only a closure of an abdominal rectum by resorting to new technical means, and no special reservoir for the accommodation of the digested matter is used in this arrangement.
All of the above-discussed operative and post-operative procedures are disadvantageous in that they subject the patients to a considerable mental stress of the presence, appearance and handling of an artifical rectum located at the front abdominal wall. Heretofore, no viable alternative to this unpleasant and often excruciating experience has been available.